BAD TO THE BONE: Lusk fossil at Paleon is changing what paleontologists know about the plesiosaur

Brooke Young photo

Inside the Paleon Museum in Glenrock, a plesiosaur model sits beside its respective fossil referred to as Serpentisuchops, which translates to “snakey crocodile-face.”  The model represents what this prehistoric and category-defying sea beast looked like in its prime.

Brooke Young photo

Paleon Museum Executive Director Don Smith holds a press release by iScience regarding a newly discovered genus of plesiosaur. The fossil that led to the discovery is housed in the Glenrock museum.

Brooke Young photo

A diagram displayed in front of the plesiosaur fossil showcases the remains of the creature (in yellow) that have been recovered and are housed in the museum.

Brooke Young photo

“Bone Biddy” Roberta (Bert) Smith delicately chips away at a fossil in the prep lab at the Glenrock Paleon Museum. 

Brooke Young

At the intersection of Birch and Fifth Streets, a weathered building that typically goes unnoticed by its community and passersby alike is about to be dubbed the birthplace of a discovery that will change the way paleontologists now view the plesiosaur.

It is Glenrock’s Paleon Museum that has recently piqued the interest of renowned paleontologists from around the globe. Although small in size, the building houses a colossal collection of dinosaur and prehistoric marine reptile fossils – including one belonging to a plesiosaur named Harold. 

And, these days, Harold is changing headlines. 

“With the plesiosaur, we knew we had a special animal. We just had to wait for the right person to put the description on it,” Glenrock Paleon Foundation Chair Stuart McCrary said. 

Dr. Scott Persons was that right person. 

The College of Charleston paleontologist initially began fulfilling his fad for digging-for-dinosaurs at the Glenrock-based museum as a child.

According to McCrary, Persons became quite interested in paleontology and his parents would award him a visit every summer to assist the crew with their digs.

As an adult, Persons has continued to visit the museum, sometimes bringing with him his paleontology and geology students, assigning each a research project. His desire to continue learning and adding to what we know about prehistoric animals is paying off.

“He came out this last summer, spent at least a full week on measuring every bone and every angle (of Harold)and then he co-authored a scientific paper with a paleontologist out of Canada who specializes in marine reptiles,” McCrary said. “He immediately knew, not even just from the vertebrae but from other portions including the jaw and the pelvis, that this was not the same plesiosaur animal you would normally find.”

According to an interview the open access journal iScience conducted with Dr. Persons, he said as a student, he was taught that all late-evolving plesiosaurs fell into one of two anatomical categories: “Those with really long necks and tiny heads, and those with short necks and really long jaws.”

“Well, our new animal totally confounds those categories,” Persons said.

McCrary further explained that the research project headed by Persons revealed that there is now a third genus and species of plesiosaur, information that was unexplored by paleontologists up until two weeks ago.

“I’m excited for us, because now we’ve got Scott (Persons) coming on a regular basis. This year was the first year he brought 12 students from College of Charleston and he put them each on an individual project within the museum,” McCrary said. “And because of that, we’re really starting to find some new stuff we didn’t know about with things we have existing here.” 

According to Persons, the scientific name of the recently discovered marine reptile is Serpentisuchops (sure-pen-ta-soo-kops) pfisterae. Serpentisuchops, which translates to “snakey crocodile-face,” is the genus, while the name of the species, pfistera, was determined based on the original founder of the fossil, Anna Pfister.

Pfister, who unearthed the animal on her ranch in eastern Wyoming in 1995, knew she’d stumbled upon something extraordinary and wanted to ensure it stayed within her home state’s borders, McCrary said.

“She basically traveled around Wyoming looking for a place to donate it and she liked us and donated it here,” he added. “Nobody at the time knew how significant it was until we realized there was no other plesiosaur known that had that many circular vertebrae with a long face. So, we knew it was an unusual species but we just didn’t have the expertise.” 

Nonetheless, the newly discovered ancient marine reptile might not have been if it were not for the efforts of the self-titled Glenrock Bone Biddies, a dedicated group of volunteers composed primarily of retired women living in the community.

“They started (volunteering) really when this museum started,” McCrary said with subtle admiration. “They’ve been here since 1995.”

Upon the fossil’s arrival to the museum in 2002, this hardworking team of volunteers set about chipping away at the rock that covered the bones, preparing the specimen for “scientific study,” as Persons put it.

The group of fossil preparators spend a good deal of their time surrounded by bones. It was during Harold’s preparation stage that the oddness of its skeleton became apparent to them.

The Bone Biddies primarily consists of Don and Roberta (Bert) Smith, Lorna Keyfauver and Chrissy Wobig. 

“We are a hidden gem and now people are finding out just what a gem we are,” Keyfauver said, paying reference to the attraction the Paleon Museum has gained since the discovery of Serpentisuchops pfisterae, or Harold. 

According to the group of volunteers, two camera crews have visited since the discovery was released to the public. 

The Glenrock Bone Biddies are proud to be a part of history. 

According to Bert, because Persons was the first to identify the new plesiosaur genus and species, the site of discovery just outside of Lusk will be documented as the first, even though this particular animal may have been unearthed in other parts of the world.

“That’s a big deal,” Bert said excitedly. 

The group of volunteers remain hopeful that this breakthrough in the world of paleontology attracts more local recognition. 

“We have far more than what we can display,” McCrary said. “What is on display is only about 10% of our collection because the rest of it is locked away in vaults. I could fill a whole other room with fossils if I had the space to do it.”

Long-time volunteer fossil preparator, tour guide and Harold-know-all Don Smith motioned to a map situated by the front door of the museum, which brightly displays pins from visitors across the globe. 

“We have had people from 14 different countries visit,” Smith said. “We are a complete museum. We can go out and find it, we can prepare it in our prep lab, put it on display and then we can reproduce it within the week.” 

Although the museum accepts donations and encourages volunteers, McCrary noted that support from the Town of Glenrock could help the group put the museum on the map and attract more tourism. 

“I would love to see the town actually sponsor a museum that includes us and the Deer Creek Museum together. Then we can go from pioneers all the way to dinosaurs. We would be one of two museums in Wyoming to do that,” he said. 

Although Harold holds the current spotlight, McCrary detailed many other recent discoveries that have the potential to make headlines, and additional support would help with that. 

“Matthew Mossbrucker, who’s the director of the Morrison Museum, is a brilliant paleontologist and he’s discovered a number of things that we didn’t know we had,” McCrary said. “Little teeth that we are finding and originally thought belonged to raptors are turning out to be baby T-Rex teeth. And, if they’re that small, they are baby T-Rex teeth from one that was still in an egg,” he added. 

According to Mossbrucker, this proves tyrannosaurus rexes were nesting in Glenrock during prehistoric times.

“Very few people have been able to find that sort of thing,” McCrary said. “All sorts of good stuff is  occurring. Up until two weeks ago the world thought there were two genuses of plesiosaur. Now there’s three.” 

It’s possible that with all of the scientific discoveries happening this rural community of about 2,500 people may be in the works of becoming the center for paleontologist visits and worldwide media requests.

For more information concerning the Paleon Museum, please visit


Glenrock Independent

Physical Address:506 W. Birch, Glenrock, WY 82637 Mailing Address: PO Box 109, Douglas, WY 82633 Phone: (307) 436-2211

The Glenrock Independent is located in the Bronco Building

Office hours: Monday, Wednesday, Friday - 10:00 a.m. to 2 p.m. Tuesday, Thursday - 9:30 a.m. - 1:30 p.m.

Subscriber Login